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    11
    <script>
        /* while(true){
            一直执行
        } */
       /*  var a=window.confirm("are you sure to down?");
        console.log(a);
        while(a){
            alert("please down")
        } */
    //   for(var a=1;a<12;a++){
    //       console.log(a);
    //   }
        var a=2;
        while( a==2){
            console.log(a);
            a++;
        }
        </script>

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